drivers/hv/channel_mgmt.c

   1 /*
   2  * Copyright (c) 2009, Microsoft Corporation.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  15  * Place - Suite 330, Boston, MA 02111-1307 USA.
  16  *
  17  * Authors:
  18  *   Haiyang Zhang <haiyangz@microsoft.com>
  19  *   Hank Janssen  <hjanssen@microsoft.com>
  20  */
  21 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  22
  23 #include <linux/kernel.h>
  24 #include <linux/sched.h>
  25 #include <linux/wait.h>
  26 #include <linux/mm.h>
  27 #include <linux/slab.h>
  28 #include <linux/list.h>
  29 #include <linux/module.h>
  30 #include <linux/completion.h>
  31 #include <linux/hyperv.h>
  32
  33 #include "hyperv_vmbus.h"
  34
  35 struct vmbus_channel_message_table_entry {
  36         enum vmbus_channel_message_type message_type;
  37         void (*message_handler)(struct vmbus_channel_message_header *msg);
  38 };
  39
  40
  41 /**
  42  * vmbus_prep_negotiate_resp() - Create default response for Hyper-V Negotiate message
  43  * @icmsghdrp: Pointer to msg header structure
  44  * @icmsg_negotiate: Pointer to negotiate message structure
  45  * @buf: Raw buffer channel data
  46  *
  47  * @icmsghdrp is of type &struct icmsg_hdr.
  48  * @negop is of type &struct icmsg_negotiate.
  49  * Set up and fill in default negotiate response message. This response can
  50  * come from both the vmbus driver and the hv_utils driver. The current api
  51  * will respond properly to both Windows 2008 and Windows 2008-R2 operating
  52  * systems.
  53  *
  54  * Mainly used by Hyper-V drivers.
  55  */
  56 void vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp,
  57                                struct icmsg_negotiate *negop, u8 *buf)
  58 {
  59         icmsghdrp->icmsgsize = 0x10;
  60
  61         negop = (struct icmsg_negotiate *)&buf[
  62                 sizeof(struct vmbuspipe_hdr) +
  63                 sizeof(struct icmsg_hdr)];
  64
  65         if (negop->icframe_vercnt == 2 &&
  66            negop->icversion_data[1].major == 3) {
  67                 negop->icversion_data[0].major = 3;
  68                 negop->icversion_data[0].minor = 0;
  69                 negop->icversion_data[1].major = 3;
  70                 negop->icversion_data[1].minor = 0;
  71         } else {
  72                 negop->icversion_data[0].major = 1;
  73                 negop->icversion_data[0].minor = 0;
  74                 negop->icversion_data[1].major = 1;
  75                 negop->icversion_data[1].minor = 0;
  76         }
  77
  78         negop->icframe_vercnt = 1;
  79         negop->icmsg_vercnt = 1;
  80 }
  81
  82 EXPORT_SYMBOL_GPL(vmbus_prep_negotiate_resp);
  83
  84 /*
  85  * alloc_channel - Allocate and initialize a vmbus channel object
  86  */
  87 static struct vmbus_channel *alloc_channel(void)
  88 {
  89         struct vmbus_channel *channel;
  90
  91         channel = kzalloc(sizeof(*channel), GFP_ATOMIC);
  92         if (!channel)
  93                 return NULL;
  94
  95         spin_lock_init(&channel->inbound_lock);
  96
  97         channel->controlwq = create_workqueue("hv_vmbus_ctl");
  98         if (!channel->controlwq) {
  99                 kfree(channel);
 100                 return NULL;
 101         }
 102
 103         return channel;
 104 }
 105
 106 /*
 107  * release_hannel - Release the vmbus channel object itself
 108  */
 109 static void release_channel(struct work_struct *work)
 110 {
 111         struct vmbus_channel *channel = container_of(work,
 112                                                      struct vmbus_channel,
 113                                                      work);
 114
 115         destroy_workqueue(channel->controlwq);
 116
 117         kfree(channel);
 118 }
 119
 120 /*
 121  * free_channel - Release the resources used by the vmbus channel object
 122  */
 123 static void free_channel(struct vmbus_channel *channel)
 124 {
 125
 126         /*
 127          * We have to release the channel's workqueue/thread in the vmbus's
 128          * workqueue/thread context
 129          * ie we can't destroy ourselves.
 130          */
 131         INIT_WORK(&channel->work, release_channel);
 132         queue_work(vmbus_connection.work_queue, &channel->work);
 133 }
 134
 135
 136
 137 /*
 138  * vmbus_process_rescind_offer -
 139  * Rescind the offer by initiating a device removal
 140  */
 141 static void vmbus_process_rescind_offer(struct work_struct *work)
 142 {
 143         struct vmbus_channel *channel = container_of(work,
 144                                                      struct vmbus_channel,
 145                                                      work);
 146
 147         vmbus_device_unregister(channel->device_obj);
 148 }
 149
 150 void vmbus_free_channels(void)
 151 {
 152         struct vmbus_channel *channel;
 153
 154         list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
 155                 vmbus_device_unregister(channel->device_obj);
 156                 kfree(channel->device_obj);
 157                 free_channel(channel);
 158         }
 159 }
 160
 161 /*
 162  * vmbus_process_offer - Process the offer by creating a channel/device
 163  * associated with this offer
 164  */
 165 static void vmbus_process_offer(struct work_struct *work)
 166 {
 167         struct vmbus_channel *newchannel = container_of(work,
 168                                                         struct vmbus_channel,
 169                                                         work);
 170         struct vmbus_channel *channel;
 171         bool fnew = true;
 172         int ret;
 173         unsigned long flags;
 174
 175         /* The next possible work is rescind handling */
 176         INIT_WORK(&newchannel->work, vmbus_process_rescind_offer);
 177
 178         /* Make sure this is a new offer */
 179         spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
 180
 181         list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
 182                 if (!uuid_le_cmp(channel->offermsg.offer.if_type,
 183                         newchannel->offermsg.offer.if_type) &&
 184                         !uuid_le_cmp(channel->offermsg.offer.if_instance,
 185                                 newchannel->offermsg.offer.if_instance)) {
 186                         fnew = false;
 187                         break;
 188                 }
 189         }
 190
 191         if (fnew)
 192                 list_add_tail(&newchannel->listentry,
 193                               &vmbus_connection.chn_list);
 194
 195         spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
 196
 197         if (!fnew) {
 198                 free_channel(newchannel);
 199                 return;
 200         }
 201
 202         /*
 203          * Start the process of binding this offer to the driver
 204          * We need to set the DeviceObject field before calling
 205          * vmbus_child_dev_add()
 206          */
 207         newchannel->device_obj = vmbus_device_create(
 208                 &newchannel->offermsg.offer.if_type,
 209                 &newchannel->offermsg.offer.if_instance,
 210                 newchannel);
 211
 212         /*
 213          * Add the new device to the bus. This will kick off device-driver
 214          * binding which eventually invokes the device driver's AddDevice()
 215          * method.
 216          */
 217         ret = vmbus_device_register(newchannel->device_obj);
 218         if (ret != 0) {
 219                 pr_err("unable to add child device object (relid %d)\n",
 220                            newchannel->offermsg.child_relid);
 221
 222                 spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
 223                 list_del(&newchannel->listentry);
 224                 spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
 225                 kfree(newchannel->device_obj);
 226
 227                 free_channel(newchannel);
 228         } else {
 229                 /*
 230                  * This state is used to indicate a successful open
 231                  * so that when we do close the channel normally, we
 232                  * can cleanup properly
 233                  */
 234                 newchannel->state = CHANNEL_OPEN_STATE;
 235         }
 236 }
 237
 238 /*
 239  * vmbus_onoffer - Handler for channel offers from vmbus in parent partition.
 240  *
 241  */
 242 static void vmbus_onoffer(struct vmbus_channel_message_header *hdr)
 243 {
 244         struct vmbus_channel_offer_channel *offer;
 245         struct vmbus_channel *newchannel;
 246         uuid_le *guidtype;
 247         uuid_le *guidinstance;
 248
 249         offer = (struct vmbus_channel_offer_channel *)hdr;
 250
 251         guidtype = &offer->offer.if_type;
 252         guidinstance = &offer->offer.if_instance;
 253
 254         /* Allocate the channel object and save this offer. */
 255         newchannel = alloc_channel();
 256         if (!newchannel) {
 257                 pr_err("Unable to allocate channel object\n");
 258                 return;
 259         }
 260
 261         memcpy(&newchannel->offermsg, offer,
 262                sizeof(struct vmbus_channel_offer_channel));
 263         newchannel->monitor_grp = (u8)offer->monitorid / 32;
 264         newchannel->monitor_bit = (u8)offer->monitorid % 32;
 265
 266         INIT_WORK(&newchannel->work, vmbus_process_offer);
 267         queue_work(newchannel->controlwq, &newchannel->work);
 268 }
 269
 270 /*
 271  * vmbus_onoffer_rescind - Rescind offer handler.
 272  *
 273  * We queue a work item to process this offer synchronously
 274  */
 275 static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
 276 {
 277         struct vmbus_channel_rescind_offer *rescind;
 278         struct vmbus_channel *channel;
 279
 280         rescind = (struct vmbus_channel_rescind_offer *)hdr;
 281         channel = relid2channel(rescind->child_relid);
 282
 283         if (channel == NULL)
 284                 /* Just return here, no channel found */
 285                 return;
 286
 287         /* work is initialized for vmbus_process_rescind_offer() from
 288          * vmbus_process_offer() where the channel got created */
 289         queue_work(channel->controlwq, &channel->work);
 290 }
 291
 292 /*
 293  * vmbus_onoffers_delivered -
 294  * This is invoked when all offers have been delivered.
 295  *
 296  * Nothing to do here.
 297  */
 298 static void vmbus_onoffers_delivered(
 299                         struct vmbus_channel_message_header *hdr)
 300 {
 301 }
 302
 303 /*
 304  * vmbus_onopen_result - Open result handler.
 305  *
 306  * This is invoked when we received a response to our channel open request.
 307  * Find the matching request, copy the response and signal the requesting
 308  * thread.
 309  */
 310 static void vmbus_onopen_result(struct vmbus_channel_message_header *hdr)
 311 {
 312         struct vmbus_channel_open_result *result;
 313         struct vmbus_channel_msginfo *msginfo;
 314         struct vmbus_channel_message_header *requestheader;
 315         struct vmbus_channel_open_channel *openmsg;
 316         unsigned long flags;
 317
 318         result = (struct vmbus_channel_open_result *)hdr;
 319
 320         /*
 321          * Find the open msg, copy the result and signal/unblock the wait event
 322          */
 323         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 324
 325         list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
 326                                 msglistentry) {
 327                 requestheader =
 328                         (struct vmbus_channel_message_header *)msginfo->msg;
 329
 330                 if (requestheader->msgtype == CHANNELMSG_OPENCHANNEL) {
 331                         openmsg =
 332                         (struct vmbus_channel_open_channel *)msginfo->msg;
 333                         if (openmsg->child_relid == result->child_relid &&
 334                             openmsg->openid == result->openid) {
 335                                 memcpy(&msginfo->response.open_result,
 336                                        result,
 337                                        sizeof(
 338                                         struct vmbus_channel_open_result));
 339                                 complete(&msginfo->waitevent);
 340                                 break;
 341                         }
 342                 }
 343         }
 344         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 345 }
 346
 347 /*
 348  * vmbus_ongpadl_created - GPADL created handler.
 349  *
 350  * This is invoked when we received a response to our gpadl create request.
 351  * Find the matching request, copy the response and signal the requesting
 352  * thread.
 353  */
 354 static void vmbus_ongpadl_created(struct vmbus_channel_message_header *hdr)
 355 {
 356         struct vmbus_channel_gpadl_created *gpadlcreated;
 357         struct vmbus_channel_msginfo *msginfo;
 358         struct vmbus_channel_message_header *requestheader;
 359         struct vmbus_channel_gpadl_header *gpadlheader;
 360         unsigned long flags;
 361
 362         gpadlcreated = (struct vmbus_channel_gpadl_created *)hdr;
 363
 364         /*
 365          * Find the establish msg, copy the result and signal/unblock the wait
 366          * event
 367          */
 368         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 369
 370         list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
 371                                 msglistentry) {
 372                 requestheader =
 373                         (struct vmbus_channel_message_header *)msginfo->msg;
 374
 375                 if (requestheader->msgtype == CHANNELMSG_GPADL_HEADER) {
 376                         gpadlheader =
 377                         (struct vmbus_channel_gpadl_header *)requestheader;
 378
 379                         if ((gpadlcreated->child_relid ==
 380                              gpadlheader->child_relid) &&
 381                             (gpadlcreated->gpadl == gpadlheader->gpadl)) {
 382                                 memcpy(&msginfo->response.gpadl_created,
 383                                        gpadlcreated,
 384                                        sizeof(
 385                                         struct vmbus_channel_gpadl_created));
 386                                 complete(&msginfo->waitevent);
 387                                 break;
 388                         }
 389                 }
 390         }
 391         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 392 }
 393
 394 /*
 395  * vmbus_ongpadl_torndown - GPADL torndown handler.
 396  *
 397  * This is invoked when we received a response to our gpadl teardown request.
 398  * Find the matching request, copy the response and signal the requesting
 399  * thread.
 400  */
 401 static void vmbus_ongpadl_torndown(
 402                         struct vmbus_channel_message_header *hdr)
 403 {
 404         struct vmbus_channel_gpadl_torndown *gpadl_torndown;
 405         struct vmbus_channel_msginfo *msginfo;
 406         struct vmbus_channel_message_header *requestheader;
 407         struct vmbus_channel_gpadl_teardown *gpadl_teardown;
 408         unsigned long flags;
 409
 410         gpadl_torndown = (struct vmbus_channel_gpadl_torndown *)hdr;
 411
 412         /*
 413          * Find the open msg, copy the result and signal/unblock the wait event
 414          */
 415         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 416
 417         list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
 418                                 msglistentry) {
 419                 requestheader =
 420                         (struct vmbus_channel_message_header *)msginfo->msg;
 421
 422                 if (requestheader->msgtype == CHANNELMSG_GPADL_TEARDOWN) {
 423                         gpadl_teardown =
 424                         (struct vmbus_channel_gpadl_teardown *)requestheader;
 425
 426                         if (gpadl_torndown->gpadl == gpadl_teardown->gpadl) {
 427                                 memcpy(&msginfo->response.gpadl_torndown,
 428                                        gpadl_torndown,
 429                                        sizeof(
 430                                         struct vmbus_channel_gpadl_torndown));
 431                                 complete(&msginfo->waitevent);
 432                                 break;
 433                         }
 434                 }
 435         }
 436         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 437 }
 438
 439 /*
 440  * vmbus_onversion_response - Version response handler
 441  *
 442  * This is invoked when we received a response to our initiate contact request.
 443  * Find the matching request, copy the response and signal the requesting
 444  * thread.
 445  */
 446 static void vmbus_onversion_response(
 447                 struct vmbus_channel_message_header *hdr)
 448 {
 449         struct vmbus_channel_msginfo *msginfo;
 450         struct vmbus_channel_message_header *requestheader;
 451         struct vmbus_channel_initiate_contact *initiate;
 452         struct vmbus_channel_version_response *version_response;
 453         unsigned long flags;
 454
 455         version_response = (struct vmbus_channel_version_response *)hdr;
 456         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 457
 458         list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
 459                                 msglistentry) {
 460                 requestheader =
 461                         (struct vmbus_channel_message_header *)msginfo->msg;
 462
 463                 if (requestheader->msgtype ==
 464                     CHANNELMSG_INITIATE_CONTACT) {
 465                         initiate =
 466                         (struct vmbus_channel_initiate_contact *)requestheader;
 467                         memcpy(&msginfo->response.version_response,
 468                               version_response,
 469                               sizeof(struct vmbus_channel_version_response));
 470                         complete(&msginfo->waitevent);
 471                 }
 472         }
 473         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 474 }
 475
 476 /* Channel message dispatch table */
 477 static struct vmbus_channel_message_table_entry
 478         channel_message_table[CHANNELMSG_COUNT] = {
 479         {CHANNELMSG_INVALID,                    NULL},
 480         {CHANNELMSG_OFFERCHANNEL,               vmbus_onoffer},
 481         {CHANNELMSG_RESCIND_CHANNELOFFER,       vmbus_onoffer_rescind},
 482         {CHANNELMSG_REQUESTOFFERS,              NULL},
 483         {CHANNELMSG_ALLOFFERS_DELIVERED,        vmbus_onoffers_delivered},
 484         {CHANNELMSG_OPENCHANNEL,                NULL},
 485         {CHANNELMSG_OPENCHANNEL_RESULT, vmbus_onopen_result},
 486         {CHANNELMSG_CLOSECHANNEL,               NULL},
 487         {CHANNELMSG_GPADL_HEADER,               NULL},
 488         {CHANNELMSG_GPADL_BODY,         NULL},
 489         {CHANNELMSG_GPADL_CREATED,              vmbus_ongpadl_created},
 490         {CHANNELMSG_GPADL_TEARDOWN,             NULL},
 491         {CHANNELMSG_GPADL_TORNDOWN,             vmbus_ongpadl_torndown},
 492         {CHANNELMSG_RELID_RELEASED,             NULL},
 493         {CHANNELMSG_INITIATE_CONTACT,           NULL},
 494         {CHANNELMSG_VERSION_RESPONSE,           vmbus_onversion_response},
 495         {CHANNELMSG_UNLOAD,                     NULL},
 496 };
 497
 498 /*
 499  * vmbus_onmessage - Handler for channel protocol messages.
 500  *
 501  * This is invoked in the vmbus worker thread context.
 502  */
 503 void vmbus_onmessage(void *context)
 504 {
 505         struct hv_message *msg = context;
 506         struct vmbus_channel_message_header *hdr;
 507         int size;
 508
 509         hdr = (struct vmbus_channel_message_header *)msg->u.payload;
 510         size = msg->header.payload_size;
 511
 512         if (hdr->msgtype >= CHANNELMSG_COUNT) {
 513                 pr_err("Received invalid channel message type %d size %d\n",
 514                            hdr->msgtype, size);
 515                 print_hex_dump_bytes("", DUMP_PREFIX_NONE,
 516                                      (unsigned char *)msg->u.payload, size);
 517                 return;
 518         }
 519
 520         if (channel_message_table[hdr->msgtype].message_handler)
 521                 channel_message_table[hdr->msgtype].message_handler(hdr);
 522         else
 523                 pr_err("Unhandled channel message type %d\n", hdr->msgtype);
 524 }
 525
 526 /*
 527  * vmbus_request_offers - Send a request to get all our pending offers.
 528  */
 529 int vmbus_request_offers(void)
 530 {
 531         struct vmbus_channel_message_header *msg;
 532         struct vmbus_channel_msginfo *msginfo;
 533         int ret, t;
 534
 535         msginfo = kmalloc(sizeof(*msginfo) +
 536                           sizeof(struct vmbus_channel_message_header),
 537                           GFP_KERNEL);
 538         if (!msginfo)
 539                 return -ENOMEM;
 540
 541         init_completion(&msginfo->waitevent);
 542
 543         msg = (struct vmbus_channel_message_header *)msginfo->msg;
 544
 545         msg->msgtype = CHANNELMSG_REQUESTOFFERS;
 546
 547
 548         ret = vmbus_post_msg(msg,
 549                                sizeof(struct vmbus_channel_message_header));
 550         if (ret != 0) {
 551                 pr_err("Unable to request offers - %d\n", ret);
 552
 553                 goto cleanup;
 554         }
 555
 556         t = wait_for_completion_timeout(&msginfo->waitevent, 5*HZ);
 557         if (t == 0) {
 558                 ret = -ETIMEDOUT;
 559                 goto cleanup;
 560         }
 561
 562
 563
 564 cleanup:
 565         kfree(msginfo);
 566
 567         return ret;
 568 }
 569
 570 /* eof */